earth ground , as shown in Figure 1. 3. Use an AC voltmeter, with 1 k potential across the resistor. /V or more sensitivity, to measure the
4. Check each exposed metallic part, and measure the voltage at each point. 5. Reverse the AC plug in the AC outlet and repeat each of the above measurements. 6. The potential at any point should not exceed 0.75 V RMS. A leakage current tester (Simpson Model 229 equivalent) may be used to make the hot checks. Leakage current must not exceed 1/2 mA. In case a measurement is outside of the limits specified, there is a possibility of shock hazard, and the receiver should be repaired and rechecked before it is returned to the customer.
Figure 1
2. X-RADIATION
WARNING :
1. The potential source of X-Radiation in TV sets is the High Voltage section and the picture tube. 2. When using a picture tube test fixture for service, ensure that the fixture is capable of handling 25.0 kV (For model with 13 inch CRT) or 30.0 kV (For model with 20 inch CRT) without causing X-Radiation.
NOTE :
It is important to use an accurate periodically calibrated high voltage meter.
5
